1. Technical Field
The present invention is directed toward staple removers and, more particularly, toward a heavy duty staple remover for removing embedded packaging staples.
2. Background Art
Staple removers for removing embedded staples from packaging materials are known in the art. They generally involve a pliers like structure wherein a tongue or anvils are inserted under the concealed back surface of an embedded staple and handles or levers connected thereto are drawn together. In this manner the tongue and anvils are caused to act cooperatively to remove the staple.
More specifically, Schafroth et al. U.S. Pat. No. 2,470,726 discloses a staple remover which comprises a flat base plate with an anvil at one end. A U-shaped handle straddles the flat base plate proximate to the open end thereof with the handle being pivotally connected to the edges of the flat base plate proximate to the anvil. At the open end of the U-shaped handle are short staple hooks disposed upon either side of the anvil. A staple is removed by placing the anvil over the exposed back portion of a staple while the staple hooks are being inserted under the concealed back portion of the staple. The handle is then depressed relative to the flat base plate and the staple hooks act in opposition to the bottom surface of the anvil to withdraw the embedded leg portions of the staple.
A staple remover according to U.S. Pat. No. 2,470,726 is difficult to operate because the shape of the handle makes it difficult to insert the staple hooks under the concealed back portion of an embedded staple. In addition, the tiny staple hooks may easily slip out from under a staple in a staple removal operation. The staple hooks may also be easily damaged and/or broken. Moreover, considerable pressure must be exerted on the handle when removing a staple because of the flat, wide structure of the anvil. Finally, packaging materials or fragile contents may be damaged in a staple removal operations using this device because of the force placed on the top of the package when the handle is depressed.
A staple remover according to U.S. Pat. Nos. 2,215,662 and 2,481,647 issued to De Generes comprises a first tongue defining a periphery surrounding a second tongue. The first tongue is attached to a handle and the second tongue is attached to a lever. Staples are removed by inserting both tongues under the concealed back surface of the embedded staple and then squeezing the lever towards the handle. This causes the second tongue to rise relative to the first and thereby pull the staple out by the force exerted upon the concealed back surface of the staple.
A stapler remover according to U.S. Pat. Nos. 2,215,662 and 2,481,647 is difficult to manufacture, in part because the handle and the lever must be spring biased to keep the first tongue properly aligned relative to the second tongue when the tongues are inserted under the concealed back surface of an embedded staple. Also, the structure is not always effective in removing staples because when the second tongue is lifted by the action of drawing the lever towards the handle, staples may bend around the second tongue instead of being drawn from the underlying packaging material.
U.S. Pat. No. 4,026,520 issued to Rothfuss et al. and U.S. Pat. No. 4,685,460 issued to Thornton pertain to surgical staple removers. Both disclosures define structures unsuitable for use in removing heavy duty staples from packaging materials. In addition, both structures would be difficult to insert under the concealed back surface of an embedded staple. Finally, both structures are difficult and expensive to manufacture which would make them especially unsuitable for heavy duty staple removing applications.
The present invention is directed toward overcoming one or more of the problems discussed above and achieving one or more of the resulting objects.